1. Field of the Invention
This invention relates to apparatus for using the energy or waves on a body of liquid, and more particularly to apparatus adapted for utilizing such energy to operate a pump.
2. Description of the Prior Art
The constant, 24-hour action of waves on a large body of water has aroused the desire of many experimenters to harness and utilize the kinetic energy causing the waves. Such devices often utilize a fixed structure to which floats are attached, and the rising and falling of the floats relative to the fixed structure is used to drive an electrical generator, pump, or other energy producing device. In such cases, the energy often is stored until it is to be used, either by electrical storage devices or by hydraulic systems in which the liquid being pumped is elevated to storage reservoirs, or by storing the liquid in pressure reservoirs or accumulators having pneumatic or mechanical spring means capable of storing potential energy for the periods of time desired.
It has also been proposed to make wave energy recovery apparatus which is free-floating on or beneath the surface of the liquid and which provides two or more floats spaced laterally from each other so that the up and down movements of the floats in response to the waves are out of phase with each other and the number of pump impulses per unit of time are accordingly multiplied.
Free floating wave pump apparatus of the character described is set forth in U.S. Pat. Nos. 4,302,161, issued Nov. 24, 1981, and 4,413,956, issued Nov. 8, 1983, both to John L. Berg, the inventor of the apparatus of the present application. In these patents, a plurality of upstanding cylinders are connected together by a subframe, with each cylinder slidably mounting a float on the outside of its cylinder, and with each float being connected to a piston within the cylinder. One way inlet and outlet valves are provided in the lower end of the cylinder and are formed so that upward movement of the piston in the cylinder draws in water and downward movement pumps out the water. While these devices provide an effective pumping action, they require that wave conditions be substantially consistent in order to achieve reasonable pumping efficiency, and the floats are prone to bind on the vertical cylinders they surround, particularly when seaweed or other debris is present.
It has been proposed to mount rocker arms on a boat, the rocker arms having floats at their outer ends which move up and down under the influence of wave action. The inner ends of the arms are utilized to operate a set of gears which, in turn, are capable of operating a generator or pump. The vertical planes in which the arms move are perpendicular to the length of the boat and hence the waves must be striking the boat at an angle in order to operate the float arms. Such structure is shown and described in U.S. Pat. No. 1,540,364 issued to Benjamin A. Roldan on June 2, 1925.
Another approach to the concept of using floats to drive reciprocal pumps may be found in U.S. Pat. No. 3,957,398 issued to Harold Lloyd on May 18, 1976. In this device, a pair of 600 foot long pontoons are mounted in spaced side-by-side relation and wave floats rest on the water in the space between the pontoons. Waves washing through the space between the pontoons are intended to raise and lower the pump floats which are directly connected to reciprocating pumps. Obviously, such device must always have the slot between the pontoons aligned with the direction from which the waves are coming in order to be operative at all.
In addition to the patents discussed above, it is believed that the patents listed below contain information which is or might be considered to be material to the examination of this application.
______________________________________ U.S. Pat. No. Inventor ______________________________________ 610,013 J. Armstrong, et al. 2,109,173 W. Herndon 3,335,667 J. Murphy 3,989,951 L. Lesster, et al. 4,076,463 M. Welczer 4,091,618 A. Jackson ______________________________________
These patents are believed to be relevant to the present invention because they were cited by the Examiners during the prosecution of applicant's above mentioned U.S. Pat. Nos. 4,302,161 and 4,413,956.